Method of desulphurization of gases



July 24, 1951 E. a. MILLER METHOD OF DESULPHURIZATION OF GASES 8Sheets-Sheet 1 Filed Oct. 14, 1947 r M M Attorneys July 24, 1951 E. B.MILLER METHOD OF DESULPHURIZATION OF GASES 8 Sheets-Sheet 2 Filed Oct.14, 1947 I///Ill.tl1. IVIIIIIIIIII IIII I! I II.

INVENTOR. E. B. Miller M M Attorneys July 24, 1951 E. a. MILLER2,561,990

METHOD OF DESULPHURIZATION 0F GASES Filed Oct. 14, 1947 8 Sheets-Sheet 5uvmvrox.

E. B. Miller Attorneys 8 Sheets-Sheet 4 6 2 7. 5 2 L \w//////// Immvrox. E. B. Miller Attornevs July 24, 1951 s. a. MILLER METHOD OFDESULPHURIZATION OF GASES Filed Oct. 14, 1947 BYMY'M July 24, 1951 E. B.MILLER METHOD OF DBSULPHURIZATION OF CASES 8 Sheets-Sheet 5 Filed Oct.14, 1947 avwmniov E. 5. Mil \8 r July 24, 1951 E. B. MILLER moo 0Fmsmnuazzmrou 0F GASES B Sheets-Sheet 6 Filed Oct. 14, 1947 grwcmtom E.B.Miller 8 Sheets-Sheet 7 Filed 001:. 14, 1947 gwuwwlow E. B. Miller y 24,1951 E. B. MILLER 2,561,990

mz'mon 0F DESULPHURIZATION or GASES Filed Oct. 14, 1947 a Sheets-Sheet a3504s 1a 0a Manooag .mqdmg H abms uogwmaoag abmg uouanag .lapa

' mmvrox. E. B. Miller mvw Attorneys Patented July 24, 1951 2,561,990METHOD OF DESULPHURIZATION OF GASES Ernest B. Miller,

Houston, Tex., assignor to Jelferson Lake Sulphur Company, a corporationof New Jersey New Orleans,

Application October 14, 1947, Serial No. 779,824

4 Claims. 1

This invention relates to the desulphurization of gases and has moreparticular reference to a method of catalytic desulphurizaticn of gasesand the recovery of sulphur therefrom.

One object of the present invention is to provide a novel method oicatalytic desulphuriza tion of gases and the recovery of sulphurtherefrom.

Another object of the invention is to provide a converter in which a,plurality of catalyzing units are successively moved into and throughone or more reaction chambers and then into and through a sulphurrecovery chamber and, finally. into and through an activation chamber inwhich they are prepared for a repetition of the cycle.

Another object 01' the invention is to provide a converter. ascharacterized above, wherein the reaction, sulphur recovery, andactivation chambers are mounted within a. pressure vessel to permitequalization of pressures within and without the chambers.

Another object oi the invention is to provide a converter in which alarge surface area of relatively thin layers of granular catalyticmaterial, oflering a minimum of resistance to the flow of gases, iscondensed into a small cubic space.

Another object of the invention is to provide a system for catalyticdesulphurization of gases and the recovery of sulphur therefrom,including a converter as characterized above, wherein means are providedfor controlling the temperature of the gases to be desulphurized duringtheir passage through the converter.

Another object of the invention is to provide a system for the catalyticdesulphurization of gases under high pressure and the recovery ofsulphur therefrom.

Another object of the invention is to provide a system, as characterizedabove. wherein means are provided for continuously heating andrecirculating a regenerating medium through the activation chamber ofthe converter and for bleeding a portion of the regenerating medium backinto the gas to be desulphurized.

Another object of the invention is to provide a system, as characterizedabove, wherein means are provided for continuously heating andcirculating a medium through the sulphur recovery chamber of theconverter to remove the sulphur from the catalyst material and includingmeans for separating the recovered sulphur from such medium.

Other objects and advantages of the invention will appear in thespecification when con idered in connection with the accompanyingdrawings, in which:

Fig. l is a side elevation showing the mounting and arrangement of theapparatus of the invention. but omitting the converter drivingmechanism' Fig. 2 is a plan view of the apparatus shown in Fig. 1;

Fig. 3 is a plan view of the converter;

Fig. 4 is a side elevation, partly in section. of the converter drivingmechanism;

Fig. 5 is a vertical sectional view of the converter; taken on line 5-5of Fig. 3, but omitting the driving mechanism;

i 6 is a horizontal sectional view of the converter, taken on line 8-8of Fig. 5, but drawn to a smaller scale;

Fig. 7 is an enlarged vertical sectional View of the seal shown in theright hand side of the upper manifold of Fig. 5;

Fig. 8 is a plan view of the seal shown in Fig. '1;

Fig. 9 is a vertical sectional view taken on line 8-4 of Fig. 8;

Fig. 10 is a horizontal sectional view. taken on line lli-M of Fig. 5;

Fig. 11 is a partial vertical sectional view of a manifold, showing thedetails of a roller;

Fig. 12 is a plan view of a tubular catalyst containlng unit Fig. 13 isa vertical sectional view, with part broken away, taken on line l3--ll01' Figure 12; and

Fig. 14 is a diagrammatic view showing the flow of the ga to bedesulphurized and the flow of the regenerating and sulphur recoveringmedia through the system.

In general, the invention comprises a method oi continuously directingthe flow of the gas to be treated into and through one or more reactionchambers, heating or cooling the gas to a. predetermined temperatureprior to its passage into each reaction chamber; continuously heatingand directing the flow of a sulphur recovery medium into and through asulphur recovery chamher, and then separating the recovered sulphur fromthe medium; continuously heating and recirculating a regenerating mediuminto and through an activation chamber; and continuously andsuccessively moving a plurality of catalyzing unit into and through thechambers.

For the purposes of illustration, the invention will be described inconnection with the catalytic desulphurization oi sour gas and therecovery of sulphur therefrom.

Referring now to the drawings, there is shown in Figs. 1 and 2, oneembodiment of apparatus and the arrangement thereof for carrying out themethod this invention. The apparatus shown includes a four-stageconverter l, two stages of which are used as reaction chambers in whichthe sour gas is brought into intimate contact with the catalyst, anotherstage is used as a recovery chamber in which the sulphur is separatedfrom the catalyst, and the remaining stage is used as an activationchamber in which the catalyst is regenerated; a heater 2 for heating thesour gas prior to it passage through the first reaction stage; a heatexchanger 2 for heating or cooling the sour gas between the first andsecond reaction stages; a heater l for heating the medium circulatedthrough the sulphur recovery stage; and a heater 5 for heating theregenerating medium prior to its e through the activating stage. Theconverter is preferably supported in a. raised position by a suitableframework, indicated at i.

The sour gas to be desulphurized is delivered, under suitable pressure.from a source of supply (not shown) to the first reaction stage heater2, by means of a pipe line I. The gas is heated in the heater to about200 C. and then passes through pipe line 8 to the first reaction stageof the converter. During its passage through the first reaction stage,the hot sour gas is brought into intimate contact with the catalyst andis partially desulphurized. From the first re action stage, thepartially desulphurized gas passes through pipe line 9 to the heatexchanger 3, where its temperature, which may have changed during itspassage through the first stage, is readjusted to 200 C. From the heatexchanger, the heated partially desulphurized gas passes through pipeline ill to the second reaction stage of the converter. During itspassage through the second reaction stage, the hot partiallydesulphurized gas is brought into intimate contact with the catalyst andthe final desulphurization takes place, leaving the gas sweet. Afterpassing through the second stage, the now sweet or desulphurized gas isdelivered, through pipe line H, to its point 0! use (not shown).

The sulphur recovery medium, preferably steam, is supplied to therecovery medium heater 4, where it is superheated to about 800 F., andfrom the heater passes through pipe line l2 into the sulphur recoverystage of the converter. During its pe through the recovery stage, thesuperheated steam is brought into intimate contact with the catalyst andvaporizes the sulphur contained therein. From the recovery stage, thesteam and sulphur vapor pass through pipe line II to a tan or blower II,by means of which the steam and vapor are recirculated through theheater {and the recovery stage. A portion of the steam and sulphur vaporis bled of! from the heater 4 by means oi a pipe line l5 and passes intoa sulphur condenser it, from which the condensed liquid sulphur may bedrained through a suitable drain valve. The sulphur condenser ispreferably of the steam cooled type and the sulphur liquefies' at about300 F. The steam is discharged !rom the condenser through a suitablepressure relief valve located in the top of the condenser.

The regenerating medium, preferably air, is supplied under suitablepressure to the regenerating medium heater 5, where it is heated toabout from 1000' F. to 1100 F., and, from the heater, passes into theactivation stage oi the converter through pipe line l1. During itspassage through the activating stage, the heated air is brought intointimate contact with the catalyst and burns ofl any remaining particlesof sulphur and impurities in the form of tars or carbonaceous mattercontained in the sour gas.

From the activation stage, the hot air, together with the burnt oi!sulphur in the tom of S01 passes through pipe line ll to a. tan orblower It, by means of which it is recirculated through the heater 5 andthe converter. A portion of the hot air with its S0: content is bled oilthe discharge line of the blower l9 and passes through pipe line 20 intothe sour gas heater 2 so that the contained sulphur may be recovered,and the oxygen contained therein may be used to oxidize the gas in thefirst stage reaction chamber. The oxygen contained in the mixture of airand which remains in the catalytic mass as it moves from the activationstage to the second reaction stage provides a part of the oxygen neededfor oxidizing the gas in the second reaction stage.

The converter is similar in construction to the dehydrator shown in myco-pending application, Ser. No. 106,108, filed October 28, 1946, forMethod of and Apparatus for Dehydrating Gas and Recovering CondensableHydrocarbons Therefrom, now Patent No. 2,507,608, issued May 16, 1950,and comprises a pressure vessel 2!; upper and lower manifolds 22, 23,fixedly mounted within the vessel; a compartmentized annular drum 24rotatably mounted with the pressure vessel between and in communicationwith the manifolds; and suitable driving mechanism for rotating theannular drum.

The pressure vessel 2i is preferably formed in two parts, an upperflanged shell or cap 25 and a lower flanged shell 26 suitably securedtogether, as by bolting, to form a. gas-tight joint.

The annular drum 24 is fixedly attached, as by means of plates 21, 28,to a central vertical shaft 20 suitably journaled in bearings carried bythe upper and lower shell members 25, 26. The mechanism for rotating theannular drum is supported on a platform 30 mounted on the upper shelf 25and includes a shaft 3i connected to the upper end of the shaft 29 by acoupling 32. The shaft 3! is driven by suitable reduction gearingmounted in a housing 33, the reduction gearing being belt-driven by amotor 8..

The rotatable annular drum 2! comprises two spaced concentric cylinders35, 36, which form the side walls; two spaced annular plates 31, ll,each secured to the top of the cylinders 35, 38, respectively form thetop of the drum, the space between the annular plates 21, 38 forming anannular opening 39 in the top of the drum; two spaced concentric annularplates 40, ll, each secured to the bottom 01' the cylinders 25, 26,respectively form the bottom of the drum, the space between the annularplates "I, ll forming an annular opening 42 in the bottom of the drum.

The rotatable annular drum is divided into a plurality oi compartmentsII by radial partitions or diaphragms II. In each of the radialcompartments l3, near the bottom thereof, there is provided a. plate 45attached to the walls of the compartment, as by welding, to form agas-tight joint.

Each plate 45 forms a support for one or more tubular catalystcontainers 4.. In the particular embodiment shown, only one suchcontainer is shown mounted in each compartment.

The catalyst containers 46 are identical in construction and, as shownin Figs. 12 and 13, each comprises two concentric tubular wire screens",ll, held in spaced relation by a purality ot longitudinal radial fins49, with the annular space between the screens closed at the bottom. Themesh of the screens is such as to retain a granular catalyst material 59in the annular space between the screens. Although the invention is notlimited thereto, it is preferred to employ a catalyst wherein granularsilica gel or a substance having substantially the same structure is thecarrier for the active material, preferably iron oxide.

Each of the containers 46 is closed at its top by means of concentrichoops 5|, 52 mounted on the concentric screens 41, 49 and a cover plate93 detachably connected to the inner hoop 52, as by screw bolts, andhaving a depending annular trough-shaped flange 54 fitting between thehoops Ii, 52. A depending annular fin 55 is secured to the flange 54 andprojects downwardly between and below the hoops 5|, 52, and fits inslots 59 formed in the upper ends of the radial fins 49, all as shown inFig. 13. The construction being such that, as the catalyst settles down,leaving a space between the top portion of the wire screens devoid ofcatalyst, the fin 55 will prevent gas from passing through the spacedevoid of catalyst. Each container 46 is detachably mounted on a nozzle51 projecting upwardly from an opening 59 formed in the plate 45, asclearly shown in Fig. 5. The nozzle 51 is secured in the opening 58. asby welding, to form a gas-tight joint.

The top and bottom manifolds 22, 23 are mounted on the top and bottom ofthe annular drum 2!, in communication with the annular openings 39, 42formed in the top and bottom of the drum. The manifolds are identical inconstruction and each is formed in the shape of an annular trough havingan annular top (or bot tom) 59 and annular side walls 69, El (see Fig.7)

A plurality of compression springs 62, mounted on brackets 63 suitablysecured to the inner walls of the vessel 2|, yieldably press the top andbottom manifolds against the top and bottom, respectively, of theannular drum. The top and bottom manifolds are held stationary relativeto the rotation of the drum by means hereinafter to be described, and,to prevent the escape of gas between the rotating drum and themanifolds, sealing ring gaskets 64 are placed at the junction of theside walls of the manifolds and the drum.

The sealing ring gaskets G4 are held in tight sealing engagement withthe top and bottom of the drum by means of annular hoops G5 whichencircle the gaskets and hold them against the side walls of themanifold. The upper (or lower) ends of the hoops 65 are secured to thetop (or bottom) plate of the manifold, as by welding. The ring gasketsare retained between the hoops 65 and the side walls 59, 5| of themanifolds by means of a plurality of circumferentially spaced threadedbolts 65, which engage the ring gaskets and the lower portions of thehoops and side walls. The ring gaskets 54 are yieldably held inengagement with the top and bottom of the drum 24 by means of aplurality of compression springs 61 mounted on stud bolts 59 secured tothe top (or bottom) of the manifolds and engaging annular plates ormembers 69 mounted on the top (or bottom) of the ring gaskets, all asclearly shown in Fig. '7.

At four circumferentially spaced points in the top and bottom manifolds,there are located seals which, by reason of the sliding contact of theradial partitions 49 against the under surface of the bottoms of theseals, divide the manifolds and drum into four sectors, each sectorgas-tight with respect to the adjacent sectors. The seals are identicalin construction and the details thereof are best shown in Figs. 7. 8 and9. Each seal includes a bottom or sealing plate 10 mounted within themanifold between spaced radial partition walls H. 12. The bottom plateI0 is yieldably urged against the top (or bottom) of the drum and restson the concentric annular plates 31, 39 which form the top of the drum(or plates 49, II which form the bottom of the drum), as shown in Fig.7. The side edges of the plate are bifurcated, as shown at 13, II, forthe reception of gasket strips 15, 18, which are yieldably pressedoutwardly against the partition walls 1!, 12 of the seal by leaf springs11, I9, as shown in Figs. 8 and 9.

The means for yieldingly pressing the bottom plate 10 of the sealagainst the top (or bottom) of the drum comprise a plurality ofcompression springs 19 mounted on projections 80, formed on the uppersurface of the plate ill. The springs 19 engage the top (or bottom) ofthe seal and are held in position by bolts 8! projecting through the top(or bottom) of the seal and coiled springs and threaded into theprojections 89 formed on the plate Hi.

Each radial partition or diaphragm 44 has a portion of its top andbottom edges extending upwardly (or downwardly) between the edges of theopenings in the top and bottom of the drum. A gasket 92 is secured onthese portions and extends above (or below) their top (or bottom) edgesand engages the under face of the bottom plate 19 of the seal.

Plates 83 are secured to the tops and bottoms of the partitions and areheld spaced therefrom by a spacer strip 84, the plates and spaces stripbeing secured to the partitions by bolts 85, The gaskets 92 are confinedbetween the partitions and the plates 83, as by means of bolts 96, andare pressed upwardly (or downwardly) against the under surface of thebottom plates 10 of the seals by means of leaf springs 91, all as shownin Fig. 9.

In order to prevent the gaskets 82 from being unduly pressed upwardly(or downwardly) when the gaskets are not engaging the bottoms of theseals. means are provided for spanning the reaches of the manifoldsbetween the seals. These means comprise spaced pairs of curved plates98, 89 which extend between and are secured to the partition walls ofthe seal, as shown in Fig. 10. The bottom surfaces of the plates 98, 89are in the same horizontal plane as the bottom surfaces of the bottomplates ill of the seals, so that, as the gaskets 82 move out ofengagement with the bottom plate of the seal, they immediately engagethe plates 89, 99.

A plurality of rollers 9|) are mounted within the top and bottommanifolds. These rollers are circumferentially spaced within themanifolds and are adapted to engage the annular plates 31, 49 which formparts of the top and bottom, respectively, of the rotatable drum. Theserollers are adapted to prevent frictional surface engagement between theside walls of the manifolds and the top and bottom of the drum. Theserollers are identical in construction and mounting and each comprises athreaded stud bolt 9| screwed into the outer side wall of the manifold;a ball race 92 fixedly mounted on the bolt; and a wheei 93 mounted onthe ball race, all as shown in Fig. 11.

Four pipes or conduits 94, 95, 96 and 91 having threaded ends projectthrough the cap of the vessel 2i and have their threaded ends secured tothe top plate of the top manifold by means of lock nuts 98 which formgas-tight joints. The pipes are welded to the cap and hold the topmanifold stationary relative to the rotation of the drum. The four pipesare circumferentially spaced with respect to the top manifold and eachis secured to and. communicates with the manitold at a point locatedbetween the seals.

Four additional pipes 90, Ill, ill and "I2. having threaded ends,project through the bottom of the vessel 21 and have their threaded endssecured to the bottom plate of the bottom manifold by means of lock nutsI" which form gas-tight joints. These pipes are welded to the bottom ofthe vessel 2| and hold the bottom manifold stationary relative to therotation of the drum. These pipes are circumferentially spaced withrespect to the bottom manifold and each is secured to and communicateswith the manifold at a point located between the seals. The width of theseals with respect to the radial compartments '48 containing thecatalyzing units is such that at all times at least one of thepartitions or diaphragms I4 is engaging the bottom plate III of the sealin gas-tight engagement.

From the foregoing, it will be readily seen that by the engagement ofthe radial portions with the seals, the manifolds and drum are dividedinto four gas-tight chambers or sectors, called, for convenience, thefirst reaction stage, the second reaction stage, the sulphur recoverystage, and the activation stage.

The drum carrying the tubular catalyst containers is rotatedcounter-clockwise, as viewed in Fig. 2, and, as it rotates, the tubularcatalyst containers are successively moved through the four stages inthe following order: the second reaction stage, the first reactionstage, the suiphur recovery stage, and the activation stage. The fourpipes 84, B5, 95 and 91 are connected to pipe lines ii, iii, i8 and i3,respectively. and the four pipes 89, Hill, Ill and III! are connected topipe lines 9, H, H and 12, respectively, by means of which the sour gas,desulphurizing medium and reactivating medium flow into and through theconverter.

The flow of the sour gas through the reaction stages, the flow of thesulphur recovery medium through the sulphur recovery stage, and the flowof the hot air through the activation stage are shown schematically inFig. 14.

The sour gas to be desulpherized, together with the bled off mixture ofair and SO: from the recirculating system for the regenerating medium,

which is the oxidant, after being heated to the optimum reactiontemperature in the first reaction stage heater, passes through pipe lineI to the converter and enters the top manifold of the first stagethrough pipe 9|. Then. it moves downwardly from the manifold through theopening in the top of the drum into the various compartments of the drumcontaining the tubular catalyst containers, as are at that timecontained within the sector forming the first reaction stage. The sourgas passes through the pervious layer of catalytic material into theinterior of the tubular container; thence, downwardly through theopening in the plate it into the bottom of the drum, and through theopening therein into the bottom manifold. From the bottom manifold, thenow partially desulphurized gas passes through pipes 99 and 9 to thesecond reaction stage heat exchanger, where the temperature of thegas,'which may have changed during its passage through the iirst stage,is

again adjusted to the optimum reaction temperature. From the secondreaction stage heat exchanger, the partially desulphurlsed gas passesthrough pipes ill and SI into the top manifold of the second reactionstage. The gas moves downwardly through the second reaction stage. in amanner similar to its downward movement through the flrst reaction stageand during its passage further desulphurlsation takes place. Afterpassing through the second reaction stage, the now sweet desulphuriaedgas passes through pipes Hill and il to its point of use or to appuratusfor further treatment.

The recovery of the sulphur from the catalytic material is effected inthe recovery stage. The recovery medium, preferably steam, is pumped, bymeans of a fan or blower M, through the recovery medium heater 4, whereit is superheated, and from the heater through pipes i2 and I02 into thebottom manifold of the recovery stage of the converter. From the bottommanifold, the superheated steam poses through the opening in the bottomof the drum into the bottoms of the various compartments as are at thattime contained within the sector forming the recovery stage; thence,upwardly through the openings in the plates 45 and up into the inte riorof the tubular catalyst containers, through the pervious layer ofcatalyst material into the compartments of the drum. As the superheatedsteam passes through the catalyst material, the sulphur is vaporized andremoved therefrom and flows along with the steam. The steam and thevaporized sulphur then pass upwardly through the opening in the top ofthe drum into the top manifold. From the top manifold, the steam andvaporized sulphur pass through pipes 91 and I! back to the fan or blowerM, by means of which they are recirculated through the heater andsulphur recovery stage of the converter. A portion of the steam andvaporized sulphur are bled from the heater and pass through pipe line l5into the sulphur condenser it, where the sulphur is liquefied andwithdrawn through a suitable drain valve located in the bottom of thecondenser. The steam escapes from the condenser through a suitablepressure relief valve located in the top thereof. By continuouslyrecirculating the stcam and sulphur vapor through the heater andrecovery stage. and admitting a sufficient amount of new steam tocompensate for the steam and sulphur vapor bled oil to the sulphurcondenser, a considerable amount of heat is saved and a highly efficientsulphur recovery working condition is obtained.

The burning oil of any runaining sulphur particles and impurities fromthe catalytic material is effected in the activation stage. Theregenerating medium, preferably, air, is pumped by means of a fan orblower l8, through the regenerative medium heater 5 and from the heaterthrough pipes ii and ill into the bottom manifold of the activationstage. From the bottom manifold, the hot air passes through the openingin the bottom of the drum into the bottoms of the various compartmentsof the drum as are at that time contained within the sector forming thereactivation stage; thence, upwardly through the openings in the plates45 and up into the interior of the tubular catalyst container, throughthe pervious layer of catalyst material into the compartments of thedrum. As the hot air passes through the catalyst material, any particlesof sulphur remaining thereon, and impurities in the form of tars orcarbonaceous matter, are burnt oi! and the sulphur flows with the hotair in the form of S02. The hot air and S02 pass through pipes 96 and IIto the recirculation fan or blower l9, by means of which they arerecirculated through the heater 5 and the converter. A portion of thehot air and S: is bled on the discharge line of the blower and passesthrough pipe line 20 into the incoming sour gas heater 2, so that thecontained sulphur may be recovered and to provide an oxidant for thfirst reaction stage. By continuously recirculating the hot air and S02through the heater 5 and the reactivation stage of the converter, andadmitting a suflicient amount of new air to compensate for the air andS02 bled off to the sour gas heater, a considerable amount of heat issaved and high regenerative action is obtained, and, too, a considerablesaving in sulphur in the form of S02 is obtained. The mixture of hot airand S02 which remains in the catalytic mass and the compartments of thedrum as they move from the reactivation to the second reaction stageprovides a part of the necessary oxidant for the second reaction stage.

By mounting the annular drum and the manifolds within a pressure vessel,the method may be carried out with high pressure gases and, too, theequalization of pressure within the drum, manifolds and vessel, permitsthe drum and manifolds to be made of lighter weight material, which addsconsiderably to the eflicient and economical operation of the converter.This equalization is accomplished by means of a small opening formed inthat portion of the pipe line 94 within the vessel 2|. It is alsoconsidered desirable to provide each of the eight pipes 94, 95, 96, 91,89, I00, II and I02 with expansion joints Ill, located a short distancefrom their points of connection to the manifolds. This may be necessary,due to the unequal temperatures of the gases and media as they passthrough the various sectors, thereby resulting in unequal expansion ofthe parts of the drum and manifolds.

From the foregoing, it will be seen that there has been provided a novelmethod of and improved apparatus i'or desulphurizing gases. The methodcomprises, broadly, the steps of continuously heating and directing theflow of a sour gas through the catalytic material at one or more pointsin its closed path; continuously heating and recirculating steam throughthe catalytic material at one point in its closed path to vaporize thesulphur therein, and bleeding oil a portion of the vaporized sulphur,condensing and recovering it: and continuously heating and recirculatingair through the catalytic material at still another point in its closedpath to regenerate the catalyst; bleeding 06 a portion of therecirculated heated air and conductin it into the heated sour gas priorto its passage through the catalyst. At this point, it may be well topoint out that the gas to be desulphurized flows through the catalyst inthe same direction in the reaction stages, viz., from the outside to theinside of the tubular containers, while the recovery and regenerativemediums flow through the catalyst in the opposite direction in therecovery and activation stages, viz., from the inside to the outside ofthe tubular containers. This reversal of flow, as it were, has animportant bearing in the practice of the method of the invention. In thereaction stages, due to the flow from outside to inside" of the tubularcontainers, a heavier deposit of sulphur is made on the materialadjacent to the outer circumference than adjacent to the innercircumference. By reversing the flow of the recovery medium, in theinstant case superheated steam, the deposited sulphur is more quicklyand efficiently vaporized. Also the impurities which have been depositedon the catalyst material are thicker or heavier on the material adjacentto the outer circumference than on the catalyst material adjacent to theinner circumference. Accordingly, by reversing the flow of theregenerating medium, in the instant case hot air, the depositedimpurities are more quickly and eificiently removed.

While the invention has been described in connection with thedesulphurization of sour gas, obviously, it is also applicable to thedesulphurization of other types of sulphur containing gases and vaporswhich are subject to the action of a suitable solid catalyst.

Obviously, the invention is not restricted to the particular embodimentthereof herein shown and described. Moreo.er, it is not indispensablethat all of the features of the invention be used conjointly, since theymay be employed advantageously in various combinations andsubcombinations.

What is claimed is:

1. In the recovery of sulphur from gases containing sulphur compoundsinvolving the contact of a catalyst with the sulphur-containing gas withresultant liberation of elemental sulphur and its deposition on thecatalyst, and subsequent treatment of the catalyst with a sulphurrecovery medium to remove the sulphur and then with a regeneratingmedium to regenerate the catalyst for further contact with thesulphurcontaining gases, the improvement which comprises rotating aseries of separated thin beds of catalyst directly in succession andsubstantially continuously relative to and through a reaction zone, asulphur recovery zone and a regenerated zone; continuously directing theflow of the sulphur-containing gas mixed with an oxidant gas throughsaid reaction zone; heating the gaseous admixture to an optimum reactiontemperature prior to its passage through the reaction zone; continuouslyWithdrawing the desulphurized gas from the reaction zone; continuouslydirecting the flow of a hot sulphur recovery medium through the sulphurrecovery zone to vaporize the liberated sulphur deposited on the bedstherein; continuously withdrawing the sulphur recovery medium togetherwith the vaporized sulphur from the sulphur recovery zone; condensingand recovering the sulphur from the the sulphur recovery medium;continuously directing the flow of a hot oxidizing medium through theregenerating zone to regenerate the catalyst; and continuouslywithdrawing the regenerating medium from the regenerating zone.

2. The method, as set forth in claim 1, wherein the direction of flow ofthe gas and oxidant admixture through the catalyst material in thereaction zone is opposite to the direction of flow of the sulphurrecovery and regenerating mediums through the catalyst material in thesulphur recovery and regenerating zones respectively.

3. In the recovery of sulphur from gases containing sulphur compoundsinvolving the contact of a catalyst with the sulphur-containing gas withresultant liberation of elemental sulphur and its deposition on thecatalyst and the subsequent treatment of the catalyst with a sulphurrecovery medium to remove the sulphur and then with a regeneratingmedium to regenerate the catalyst for further contact with thesulphurcontaining gas, the improvement which comprises rotating 0.series of separated thin beds of catalyst directly in succession andsubstantially continuously relative to and through a succession ofreaction zones, a sulphur recovery zone and a regenerating zone;continuously directing the flow oi the sulphur-containing gas mixed withan oxidant gas in succession and in series through said reaction zones;heating the gaseous admixture to an optimum reaction temperature priorto its passage through each of the reaction zones; continuouslywithdrawing the desulphurized gas (mm the last one of the reactionzones; continuously directing the flow or a hot sulphur recovery mediumthrough the sulphur recovery zone to vaporize the liberated elementalsulphur deposited on the beds therein; continuously withdrawing thesulphur recovery medium together with the vaporized suiphur from thesulphur recovery zone; condensing and recovering the sulphur from thesulphur recovery medium; continuously directingthe flow o! a hotoxidizing medium through the regenerating zone to regenerate thecatalyst; and continuously withdrawing the regenerating medium from theregenerating zone.

4. The method. as set forth in claim 8, wherein the direction 01' theseries flow of the gas and oxidant admixture is opposite to thedirection of rotation 01 the catalyst beds, whereby the admixture willalways make its last passage through freshly regenerated catalyst beds.

ERNEST B. MILLER.

REFERENCES CITED The following references are or record in the file orthis patent:

UNITED STATES PATENTS Number Name Date 1,507,105 Carstens et a1 Sept. 2,1924 1,773,294 Benner Aug. 19, 1980 1,922,872 Thompson Aug. 15, 19332,246,345 Campbell June 17, 1941 2,337,956 Yerrick et a] Dec. 28, 19432,384,926 Jones Sept. 18, 1945 2,425,754 Murphree et al Aug. 19, 194'!2,436,225 Ogorzaly et al Feb. 17, 1948 FOREIGN PATENTS Number CountryDate 267,138 Great Britain Dec. 15, 1927

1. IN THE RECOVERY OF SULPHUR FROM GASES CONTAINING SULPHUR COMPOUNDSINVOLVING THE CONTACT OF A CATALYST WITH THE SULPHUR-CONTAINING GAS WITHRESULTANT LIBERATION OF ELEMENTAL SULPHUR AND ITS DEPOSITION ON THECATALYST, AND SUBSEQUENT TREATMENT OF THE CATALYST WITH A SULPHURRECOVERY MEDIUM TO REMOVE THE SULPHUR AND THEN WITH A REGENERATINGMEDIUM TO REGENERATE THE CATALYST FOR FURTHER CONTACT WITH THESULPHURCANTAINING GASES, THE IMPROVEMENT WHIC CCOMPRISES ROTATING ASERIES OF SEPARATED THIN BEDS OF CATALYST DIRECTLY IN SUCCESSION ANDSUBSTANTIALLY CONTINUOUSLY RELATIVE TO AND THROUGH A REACTION ZONE, ASULPHUR RECOVERY ZONE AND A REGENERATED ZONE; CONTINUOUSLY DIRECTING THEFLOW OF THE SULPHUR-CONTAINING GAS MIXED WITH AN OXIDANT GAS THROUGHSAID SEACTION ZONE; HEATING THE GASEOUS ADMIXTURE TO AN OPTIMUM REACTIONTEMPERATURE PRIOR TO ITS PASSAGE THROUGH THE REACTION ZONE; CONTINUOUSLYWITHDRAWING THE DESULPHURIZED GAS